HELP - Same ECID being given to different Users !

[LeeBu]

Hello.

I am just wanting to share with you an issue we are seeing that we cannot get to the bottom of, nor can Adobe Support tell us what is going on because they don't know how to replicate the issue we are seeing.

• We are using Adobe campaign to send emails to recipients. Each recipient has a unique customer number and that customer number is dynamically included in the clickable links in the body of the email as a query string parameter.
• When a recipient clicks through from the email they are taken to our web page and we drop 1st party necessary cookies as per Adobe's out of the box recommendations (using the Identity service) as well as our own 1st party cookies. 
• One of the cookies we drop (if it does not already exist) is one that scrapes the value of the customer number (from clickable email link) and places it in a cookie. So we know, when someone clicks through who they are and what they are browsing.
• What we are seeing is that in a small number of cases. Different recipients who have clicked through from emails are being given the SAME ECID.
• We know they are different individuals because the URL obviously contains their customer number and also we drop an additional browser/device cookie as well for other reasons I won't go into.

Below is a screenshot of an example. evar200 is the customer number. You will notice that really weirdly what appears to be 2 different users, even got the same session ID at 13:01 and 13:29 too

I am just wondering if anyone else see's such unexplained behaviour of if you have any thoughts as to why this may be happening ?

Regards

Lee

[yuhuisg]

One common reason is that different people share the same device. This would be quite uncommon, though, since most people in developed countries are unlikely to share devices... though I suppose it could be possible for people in the same household to use one computer between themselves with a common OS login / web browser profile.

Having said that...

1. How often does your problem happen?
2. What are the Allocation and Expire On settings for this eVar200?

[MandyGeorge]

My first thought for this is, it's possible that people are forwarding the email to their friends/family. Then when that person clicks on the email, I would assume it would give them both the same ID. Another possibility would be one person using multiple browsers or devices. 

[gautham_madala]

Unless different users use same device without clearing their cookies this is not possible otherwise.

[igupta]

If it's only one instance, can this be a rare case of hash collision?

[Sukrity_Wadhwa]

Hi @LeeBu,

Were you able to resolve this query with the help of the provided solutions, or do you still need further assistance? Please let us know. If any of the answers were helpful in moving you closer to a resolution, even partially, we encourage you to mark the one that helped the most as the 'Correct Reply.'

Thank you!

[Krishna_Musku]

If two users access the application using the same device or browser, they will be assigned the same ECID, as it's tied to the client, not the individual user.